Yes, I know @anthracite is an old dude, and so he may not immediately understand what this is about. Think of it as a small tribute because I like the username.
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For those who care about details for whatever reason, anthracite is the highest energy yielding coal in existence, and it's mostly black. So an Xyz monster seemed fitting, plus overlaying just feels like something rocks would do. And if course, due to its high energy yield, it can keep a FIRE going for a long time, though hopefully not too many Pyros get their hands on it.
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Yugioh has veritable geological layers of Rock monsters. In fact Yugi (not Yami) uses a Rock deck. But out of all of them, Barrel Rock — https://yugipedia.com/wiki/Barrel_Rock — is probably the heaviest mover and shaker, or at least he looks the looks the part.
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For those who care about details for whatever reason, anthracite is the highest energy yielding coal in existence, and it's mostly black. So an Xyz monster seemed fitting, plus overlaying just feels like something rocks would do. And if course, due to its high energy yield, it can keep a FIRE going for a long time, though hopefully not too many Pyros get their hands on it.
*
Yugioh has veritable geological layers of Rock monsters. In fact Yugi (not Yami) uses a Rock deck. But out of all of them, Barrel Rock — https://yugipedia.com/wiki/Barrel_Rock — is probably the heaviest mover and shaker, or at least he looks the looks the part.